The development of smaller optical and electro-optical devices having improved specifications has been investigated to a certain extent. In some applications, it was found useful to use PICs, i.e. devices which involve the use of light directly on a photonic chip in a manner analogous to the use of electricity in electronic chips.
These PICs are generally configured to transmit light from a photonic device to another and to process it via waveguides present on the photonic chip. In some PICs, the incoming light is received from an external waveguide via direct coupling to the optical port of one of the waveguides of the PIC. Such direct coupling of the incoming light into the waveguide of the photonic chip can be challenging since these waveguides typically have dimensions much smaller than those of the external waveguide. To address this challenge, it was known to focus light exiting from the external waveguide to a small spot and to precisely position the external waveguide so as to provide the small spot right onto the optical port of the waveguide for direct coupling of the incoming light into the PICs.
Although some techniques exist to align a laser beam relative to the optical axis of an optical element, such as the one described in U.S. Pat. No. 6,512,642 (BOURCIER et al.), there remains room for improvement, particularly in providing a method for optically coupling a waveguide array to a PIC.